function tab(){ 
    this.res = 0;
        this.button = document.querySelectorAll("a");
        this.ul = document.querySelectorAll("ul");

    this.btn = function(){
    
        this.button.forEach((v,i)=>{
            v.onclick = ()=>{

                this.button[this.res].classList.remove("active");
                console.log()

                v.classList.add("active");

                this.ul[this.res].style.display = "none"

                this .ul[i].style.display ="block"

                this.res = i
            }
        })

    }
}